Photovoltaic product and method of manufacturing the same

ABSTRACT

The present disclosure pertains to a photovoltaic product ( 1 ), comprising a foil with a photovoltaic layer stack ( 10 ) and an electrically conductive layer stack ( 20 ) that supports the photovoltaic layer stack and that in an operational state provides for a transport of electric energy generated by the photovoltaic layer stack to an external load. The electrically conductive layer stack ( 20 ) comprises a first and a second electrically conductive layer ( 21, 22 ) and an electrically insulating layer ( 23 ) arranged between the first and the second electrically conductive layer, wherein the photovoltaic layer stack ( 10 ) has first electrical contacts (PI, P 2 ) of a first polarity that are electrically connected to the first electrically conductive background domain ( 210 ) and has second electrical contacts (N 1 , N 2 ) of a second polarity opposite to said first polarity that are electrically connected to the first contact areas ( 211 ), and wherein the second electrically conductive background domain ( 220 ) and one or more of the second contact areas ( 221 ) serve as electric contacts for the output clamps.

CROSS-REFERENCE TO RELATED APPLICATIONS

This patent application is a U.S. National Phase of PCT InternationalApplication No. PCT/NL2019/050850, filed Dec. 18, 2019, which claimspriority to European Application No. 18213589.7, filed Dec. 18, 2018,which are both expressly incorporated by reference in their entireties,including any references contained therein.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention pertains to a photovoltaic product.

The present invention further pertains to a method of manufacturing thesame.

Related Art

Solar energy is becoming more and more important as a source of electricenergy. To limit costs it is desired that installation photovoltaicsystems can take place efficiently. CA2691452 specifies a solar panelsystem comprising a plurality of solar panels to be arranged on a roof.The panels need to be properly connected to a power conversion module.As the number of panels and their arrangement depends on the size andshape of the roof providing the proper connections to achieve the properinput voltage for the power conversion module has to take placecarefully, and may be time consuming.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a photovoltaicproduct that facilitates a more easy installation.

It is a further object of the present invention to provide a method formanufacturing such a photovoltaic product.

According to the first object, a photovoltaic product is provided asclaimed in claim 1, that comprises a foil with a photovoltaic layerstack and an electrically conductive layer stack. The electricallyconductive layer stack supports the photovoltaic layer stack and in anoperational state provides for a transport of electric energy generatedby the photovoltaic layer stack to an external load.

The electrically conductive layer stack comprises a first and a secondelectrically conductive layer and an electrically insulating layerarranged between the first and the second electrically conductive layer.The electrically insulating layer may serve as a carrier for thephotovoltaic product. Alternatively or additionally another layer mayserve as a carrier.

The first electrically conductive layer comprises a first electricallyconductive background domain and a first plurality of laterallydistributed, mutually distinct contact areas which are electricallyinsulated from the first electrically conductive background domain.

The second electrically conductive layer also comprises a secondelectrically conductive background domain and a second plurality oflaterally distributed, mutually distinct contact areas which areelectrically insulated from the second electrically conductivebackground domain.

The electrically conductive layer stack further comprises a firstplurality of laterally distributed electrically conducting vias thatelectrically interconnect respective ones of the first plurality ofcontact areas with the second electrically conductive background domain.

The electrically conductive layer stack still further comprises a secondplurality of laterally distributed electrically conducting vias thatelectrically interconnect respective ones of the second plurality ofcontact areas with the first electrically conductive background domain.

The photovoltaic layer stack has first electrical contacts of a firstpolarity that are electrically connected to the first electricallyconductive background domain and has second electrical contacts of asecond polarity opposite to said first polarity that are electricallyconnected to the first contact areas. The second electrically conductivebackground domain and one or more of the second contact areas serve aselectric contacts for the output clamps.

The photovoltaic product of claim 1 facilitates installation onarbitrary dimensioned roofs, as it is provided as a foil that can be cutinto the size of the roof on which it is to be installed and providesfor a predetermined output voltage regardless how it is cut. It mayfurther be desired to restrict an output current delivered throughconnection clamps.

In an embodiment of the photovoltaic product the background domain ofthe first and/or the second electrically conductive layer is partitionedinto mutually separate background domain portions which are separatedfrom each other through an elongate region free from electricallyconductive material extending in a direction transverse to anarrangement direction in which the photovoltaic units succeed eachother. In that case a respective pair of output clamps may be attachedat each lateral portion of the photovoltaic product corresponding to aproper background domain portions so that the current delivered througheach pair of clamps is a portion of the current generated by thephotovoltaic product.

In an embodiment of the photovoltaic product, the second contact areasare at least twice as large as the first contact areas. This furtherfacilitates the installation of the product in that it is relativelyeasy to find the second contact areas when interconnecting the productto a power conductor. A large second contact area also contributes to alow electrical resistance in the connection with the power conductor.The electrical connection of a power conductor with the secondelectrically conductive background domain will be relatively easy, asthe latter provides for sufficient space available for connection.

It is noted that the first contact areas may be smaller, as the lattermay be connected with respective contacts of the photovoltaic layerstack in a well aligned lamination process. Also the role of theelectrical resistance is less important as the photovoltaic layer stackmay be interconnected with a large number of such first contact areas.The electrical connection of the photovoltaic layer stack with the firstelectrically conductive background domain will also be relatively easy,as the latter provides for sufficient space available for connection.

In an embodiment, the photovoltaic layer comprises a plurality ofphotovoltaic units that are arranged in an arrangement direction,wherein mutually subsequent photovoltaic units share a respective commonelectrical contact. As in this arrangement mutually subsequentphotovoltaic units share a respective common electrical contact, alarger surface area remains available for photovoltaic conversion.

In an embodiment diodes are arranged between the first electricalcontacts and the first electrically conductive background domain and/orbetween the second electrical contacts and the first contact areas,wherein the diodes are biased in accordance with the current directionas determined by the photovoltaic units in their normal operationalstate. The diodes prevent a flow of electric current in the directionopposite to the direction of the normal operational state, and therewithavoid a loss of energy that and possible damage that could otherwiseoccur if a photovoltaic unit is in a non-functional state, for exampledue to a shadow cast on that unit.

A method of manufacturing a photovoltaic product as claimed hereincomprises providing a photovoltaic layer stack, providing anelectrically conductive layer stack and laminating the photovoltaiclayer stack on the electrically conductive layer stack.

The photovoltaic layer stack is provided with a plurality ofphotovoltaic units and with first electrical contacts of a firstpolarity as well as second electrical contacts of a second polarityopposite to said first polarity.

Providing an electrically conductive layer stack comprises providing aninsulating layer with a first and a second electrically conductive layerat a respective one of mutually opposite surfaces of the insulatinglayer. The insulating layer may also serve as a carrier for the productto be manufactured.

The electrically conductive layer stack is provided with a firstplurality of laterally distributed electrically conducting vias thatelectrically interconnect the first and the second electricallyconductive layer. The electrically conductive layer stack is alsoprovided with a second plurality of laterally distributed electricallyconducting vias that electrically interconnect the first and the secondelectrically conductive layer. The first and the second plurality ofvias may for example be provided by a combination of a first processstep wherein holes are drilled, e.g by laser drilling, at the locationof the vias and a subsequent second process step wherein the holes arefilled with an electrically conductive material. Alternatively, anelectrically conductive material may be injected directly to form thevias.

Providing an electrically conductive layer stack comprises removingmaterial of the first electrically conductive layer along a contour of azone around each via of the first plurality. Therewith the firstelectrically conductive layer is partitioned into a first electricallyconductive background domain and a first plurality of laterallydistributed, mutually distinct contact areas which are electricallyinsulated from the first electrically conductive background domain. Itis noted that this step and the step of providing the vias may bereversed in order.

Providing an electrically conductive layer stack further comprisesremoving material of the second electrically conductive layer along acontour of a zone around each via of the second plurality. Therewith thesecond electrically conductive layer is partitioned into a secondelectrically conductive background domain and a second plurality oflaterally distributed, mutually distinct contact areas which areelectrically insulated from the second electrically conductivebackground domain. Likewise this step and the step of providing thesecond vias may take place in a reverse order.

Laminating comprises interconnecting the first electrical contacts ofthe photovoltaic layer stack with the first electrically conductivebackground domain of the first electrically conductive layer andinterconnecting the second electrical contacts to respective firstcontact areas of the first electrically conductive layer.

Therewith the claimed product is obtained in an efficient manner. It isnoted that the photovoltaic layer stack and the electrically conductivelayer stack may be manufactured independently of each other, at mutuallydifferent locations for example and lamination may take place at againanother location for example.

The method may comprise arranging diodes at the first electricallyconductive background domain at the locations determined forinterconnection with the first electrical contacts of the photovoltaiclayer stack. Alternatively, or additionally, diodes may be arranged atthe locations of the first contact areas for interconnection with thesecond electrical contacts of the photovoltaic layer stack. When thephotovoltaic layer stack and the electrically conductive layer stack aresubsequently laminated, it is achieved as a side result that the diodesare arranged between the first electrical contacts and the firstelectrically conductive background domain and/or between the secondelectrical contacts and the first contact areas.

An embodiment of the method comprises applying a layer of a polymer meltmaterial at an interface between the photovoltaic layer stack and theelectrically conductive layer stack. This facilitates a hot laminationprocess.

An embodiment of the method comprises providing a protective layer overthe second electrically conductive layer. The protective layer providesfor an electric insulation of the second electrically conductivebackground domain and the second plurality of laterally distributed,mutually distinct contact areas, but allows them to be exposed forconnection to clamps of electric conductors to a load, or to an electricconversion device. To facilitate an identification of the locations ofsecond contact areas, the protective layer may be provided with markingsindicative for these locations.

In the process of installation, the method may further compriseseparating a lateral portion of the photovoltaic foil. At one side, thecut out portion may be separated from the remainder along a line betweenmutually subsequent photovoltaic units.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects are described in more detail with reference tothe drawing. Therein:

FIG. 1 schematically shows a photovoltaic product.

FIGS. 1A and 1B show a part of the photovoltaic product at mutuallyopposite sides in more detail

FIGS. 2A, 2AA, 2B and 2C schematically show a method of manufacturing aphotovoltaic product. Furthermore, FIG. 2AB is a symbolic representationof a photovoltaic layer stack in the photovoltaic product to bemanufactured.

FIGS. 3A-3E, 3F, 3FF, 3G, 3GG, 3H and 3HH show steps of the method inmore detail.

FIG. 3I1, 3I2 show an alternative for a step illustrated in FIG. 3E.

FIGS. 4A and 4B schematically show a photovoltaic product obtained aftera lamination step. Therein FIG. 4B shows a top-view of the productaccording to IVB in FIG. 4A

FIGS. 5A and 5B schematically show a photovoltaic product which isseparated as a lateral portion from the product of FIGS. 4A and 4B.Therein FIG. 5B shows a bottom-view of the product according to VB inFIG. 5A

FIGS. 6A and 6B schematically show a result of a further step S6.Therein FIG. 6B shows a bottom-view of the product according to VIB inFIG. 6A

FIGS. 7A and 7B schematically show an alternative version said furtherstep. Therein FIG. 7B shows a bottom-view of the product according toVIIB in FIG. 7A.

FIG. 8, 8A, 8B schematically show a portion of an exemplary photovoltaiclayer stack

FIG. 9A shows an exemplary method to provide the photovoltaic layerstack of FIGS. 8, 8A and 8B with electrical connections. An alternativeapproach is shown in FIG. 9B, 9C.

DETAILED DESCRIPTION OF EMBODIMENTS

Like reference symbols in the various drawings indicate like elementsunless otherwise indicated.

FIG. 1 schematically shows a photovoltaic product 1, that comprises afoil with a photovoltaic layer stack 10 with a substrate 12 and anelectrically conductive layer stack 20 that supports the photovoltaiclayer stack. In an operational state of the photovoltaic layer stack itprovides for a transport of electric energy generated by thephotovoltaic layer stack to be provided to an external load, for examplevia output clamps 30P, 30N.

The electrically conductive layer stack 20 comprises a first and asecond electrically conductive layer 21, 22 and an electricallyinsulating layer 23 arranged between the first and the secondelectrically conductive layer. The electrically insulating layer 23 isfor example a polymer layer with a thickness of a few tens to a fewhundreds of micron, e.g. a PET or a PEN layer, and the electricallyconductive layers 21, 22 may be provided of a metal layer having athickness of a few to a few tens of micron, e.g. aluminum or copperlayers with a thickness of 15 micron.

As shown in more detail in FIG. 1A, the first electrically conductivelayer 21 comprises a first electrically conductive background domain 210and a first plurality of laterally distributed, mutually distinctcontact areas 211 which are electrically insulated from the firstelectrically conductive background domain 210. In the embodiment shownthis is achieved in that contact areas 211 are bounded by a contour 211c wherein material of the first electrically conductive layer 21 isremoved.

Analogously, as shown in more detail in FIG. 1B, the second electricallyconductive layer 22 comprises a second electrically conductivebackground domain 220 and a second plurality of laterally distributed,mutually distinct contact areas 221 which are electrically insulatedfrom the second electrically conductive background domain 220. Likewise,this is achieved in that contact areas 221 are bounded by a contour 221c wherein material of the second electrically conductive layer 22 isremoved.

It would alternatively be possible to apply the pattern of contact areaswithin the background domain by printing an electrically conductivematerial in that pattern.

The electrically conductive layer stack 20 also comprises a firstplurality 24 of laterally distributed electrically conducting vias thatelectrically interconnect respective ones of the first plurality ofcontact areas 211 with the second electrically conductive backgrounddomain 220. The electrically conductive layer stack 20 further comprisesa second plurality 25 of laterally distributed electrically conductingvias that electrically interconnect respective ones of the secondplurality of contact areas 22) with the first electrically conductivebackground domain 210.

The photovoltaic layer stack 10 has first electrical contacts P1, P2 ofa first polarity that are electrically connected to the firstelectrically conductive background domain 210. The photovoltaic layerstack 10 has second electrical contacts N1, N2 of a second polarityopposite to the first polarity that are electrically connected to thefirst contact areas 211. The second electrically conductive backgrounddomain 220 and one or more of the second contact areas 221 serve aselectric contacts for the output clamps 30N, 30P.

FIGS. 2A, 2AA, 2B and 2C schematically shows a method of manufacturing aphotovoltaic product. FIGS. 2A and 2AA show a first main step S1 of themethod, wherein a photovoltaic layer stack 10 is provided that has aplurality of photovoltaic units 11A, 11B, 11C and has first electricalcontacts P1, P2 of a first polarity and second electrical contacts N1,N2 of a second polarity opposite to said first polarity. FIG. 2A shows abottom view and FIG. 2AA shows a side view according to IIAA in FIG. 2A.

FIG. 2AB is a symbolic representation of the photovoltaic layer stack10. As shown therein, each photovoltaic units 11A, 11B, 11C comprises aplurality N of serially arranged photodiodes Dp. The number N, e.g. in arange from 20 to 50, determines the output voltage of each unit.

FIG. 2B schematically shows a second main step S2, wherein anelectrically conductive layer stack 20 is provided. FIG. 2B shows theelectrically conductive layer stack 20 in a view corresponding to theview of FIG. 2AA.

FIG. 2C schematically shows a third main step S3, wherein thephotovoltaic layer stack 10 is laminated on the electrically conductivelayer stack 20.

Exemplary steps comprised in main step S2 are shown in more detail inFIGS. 3A-3E, 3F, 3FF, 3G and 3GG.

FIG. 3A schematically shows step S21 of providing an insulating layerwith a first and a second electrically conductive layer 21, 22 at arespective one of mutually opposite surfaces of the insulating layer 23.

FIG. 3B, 3C shows steps S22, S23, wherein a first and a second pluralityof laterally distributed electrically conducting vias 24, 25 areprovided that electrically interconnect the first and the secondelectrically conductive layer 21, 22. In the embodiment shown, FIG. 3Bshows a first stage S22, wherein openings 24 o, 25 o are drilled, forexample by laser drilling. FIG. 3C shows a second stage S23, wherein theopenings 24 o, 25 o are filled with an electrically conductive materialto form the electric connections 24, 25.

FIG. 3D shows a step S24 of partitioning the first electricallyconductive layer into a first electrically conductive background domain210 and a first plurality of laterally distributed, mutually distinctcontact areas 211 which are electrically insulated from the firstelectrically conductive background domain. In the embodiment shown, thisis achieved in that material of the first electrically conductive layer21 is removed along a contour 211 c of a zone around each via of thefirst plurality 24. Also in step S24, the second electrically conductivelayer is partitioned into a second electrically conductive backgrounddomain 220 and a second plurality of laterally distributed, mutuallydistinct contact areas 221 which are electrically insulated from thesecond electrically conductive background domain. In the embodimentshown this is achieved by removing material of the second electricallyconductive layer along a contour 212 c of a zone around each via of thesecond plurality 25.

Alternatively, the electrically conductive layer stack may be obtainedby first providing the openings 24, 25 in the insulating layer 23,subsequently applying a metal layer (e.g. by plating) over the exposedsurfaces of the insulating layer 23, and subsequently insulating thecontact areas from the background area, e.g. by laser ablation.

As shown in FIG. 2C, laminating S3 comprises interconnecting the firstelectrical contacts P1, P2 of the photovoltaic layer stack 10 with thefirst electrically conductive background domain 210 of the firstelectrically conductive layer 21 and interconnecting the secondelectrical contacts N1, N2 to respective first contact areas 211 of thefirst electrically conductive layer 21.

FIG. 3E shows an optional step S25 of the method wherein diodes D1, D2are arranged at the first electrically conductive background domain 210at the locations determined for interconnection with the firstelectrical contacts P1, P2 of the photovoltaic layer stack 10.Alternatively or additionally, diodes may be arranged at the locationsof the first contact areas 211 for interconnection with the secondelectrical contacts N1, N2 of the photovoltaic layer stack 10. In thisexample the first contact areas are provided with metal contact elementsC1 C2 having dimensions corresponding to those of the diodes.

FIG. 3F shows an optional step S26 of the method wherein a layer 27 of apolymer melt material is applied on the first electrically conductivelayer 21 as an interface between the electrically conductive layer stack20 and the photovoltaic layer stack 10 to be laminated therewith. FIG.3FF shows a top view according to IIIFF in FIG. 3F. As shown therein,layer 27 is patterned to expose the metal contact elements C1, C2 andthe diodes D1, D2.

FIGS. 3G and 3GG show a further optional step S27 of the method. FIG.3GG shows a top view according to IIIGG in FIG. 3G. In step S27 aprotective layer 28 is provided over the second electrically conductivelayer 22. Optionally, as can best be seen in FIG. 3GG the protectivelayer 28 is provided with markings 281 indicative for the location ofone or more of the contact areas 221 in the second electricallyconductive layer 22.

FIG. 3H shows in more detail step S3, wherein the photovoltaic layerstack 10 is laminated on the electrically conductive layer stack 20.FIG. 3HH shows a bottom view of the photovoltaic layer stack 10according to IIIHHH in FIG. 3H.

FIGS. 4A and 4B schematically show the photovoltaic product 1 obtainedafter the lamination. Therein FIG. 4B shows a top-view of the productaccording to IVB in FIG. 4A.

FIG. 4B also shows that as a further, optional step S4, a lateralportion of the photovoltaic product may be separated, for example alongthe contour pointed to by the arrow S4 to fit to a particularapplication, for example the dimensions of a roof on which the separatedphotovoltaic product is to be installed. Basically any contour may bechosen. Regardless the form of the separated portion, the output voltagewill have a fixed value, which is determined by the number an ofphotodiodes Dp in each photovoltaic unit. Therewith assembly of thepanels can take place with standard tools and safety measures, withouthaving to take into account exceptional worst case circumstances thatcould prevail in conventional products if a very high number of cells isserially arranged. Preferably, the separated portion has at least oneedge CE of its contour to include at least a portion of a row ofelectrical contacts, P2 in this example, but does not include a portionof a further photovoltaic unit beyond that row in an outward direction.The edge CE may for example extend along a centerline CTR through therow of contacts. Depending on the application it may not always bepossible to also select the opposite edge of the contour accordingly, asis shown for example in FIG. 4B for the left side of the contour, whichextends through the photovoltaic unit 11A. This implies that thisphotovoltaic unit 11A does not contribute to the functioning of theseparated photovoltaic product. Nevertheless it, it does not impair thefunctioning of the other photovoltaic units 11B, 11C and it may remainfor esthetical reasons. When defining the contour, it may becontemplated in which orientation the photovoltaic product can best bearranged on a roof for example to minimize a loss in efficiency due to apartitioned photovoltaic unit.

FIGS. 5A and 5B schematically show the separated photovoltaic product1A. Therein FIG. 5B shows a bottom-view of the product according to VBin FIG. 5A. As a further step S5, a side protection 40 is providedaround the edges of the separated photovoltaic product 1A. Melting aside protection, glob top materials, e.g. as provided by Epotek, arubber strip or other methods are possible for this purpose.

FIGS. 6A and 6B schematically show a further step S6. Therein FIG. 6Bshows a bottom-view of the product according to VIB in FIG. 6A. In stepS6 a first output clamp 30P is connected with a contact area 221 formedin the second electrically conductive layer 22. A second output clamp30N is connected with the electrically conductive background domain 220formed in the second electrically conductive layer 22. To this end, theclamps 30P, 30N, may for example be pressed through the protective layer28 against their respective portion of the second electricallyconductive layer 22. Alternatively, a solder connection may be providedas the electrical and mechanical contact between the clamps 30P, 30N,and their respective portion 221, 220 of the second electricallyconductive layer 22. Before providing the connection, a portion of theprotective layer 28 may be removed to expose those portions 221, 220 ofthe second electrically conductive layer 22. Optionally, as shown inFIG. 3GG, markings 281 on the protective layer 28 may serve as aguidance when performing step S6.

As noted above, regardless the dimensions of the separated photovoltaicproduct 1A, the output voltage has a fixed value. It may be desiredhowever to limit the current which is delivered at the output clamps.This may for example be the case if the dimension of the separatedphotovoltaic product 1A in a direction transverse to the arrangementdirection of the photovoltaic units 11A, 11B, etc is relatively large,in that case it can be decided to partition the background domain 220 ofthe first or the second electrically conductive layer 22 into mutuallyseparate background domain portions, for example by removing material ofthe second electrically conductive layer 22 along an elongate regionextending in the arrangement direction, e.g. by ablation throughirradiation with a laser beam or by etching. This may for example takeplace in a manufacturing stage, for example during execution of stepS24. The location of the regions where background domain portions areseparated from each other may for example be indicated as furthermarkings on the protective layer 28.

FIG. 3I1, 3I2 show an alternative way of arranging the diodes D1, D1′.Therein FIGS. 3I1 shows a cross-section and 3I2 shows a top-view of theelectric support layer at a side where the photovoltaic stack is to bearranged. In the embodiment shown therein, the first electricallyconductive layer 21 is provided with additional contact zones 213 forconnection with the photovoltaic stack. The additional contact zones 213are electrically insulated from the background domain 220 for example bya contour 213 c where material of the electrically conductive layer 21is removed, or is converted into an electrically non-conductivematerial. The diodes D1, D1′ bridge the contour, having one terminalconnected to the background domain 210 and another terminal connected tothe contact zone 213.

FIGS. 7A and 7B schematically show an alternative version S6A of furtherstep S6 wherein the background domain 220 of the second electricallyconductive layer 22 is partitioned into mutually separate backgrounddomain portions 220A, 220B by the elongate region 225. Therein FIG. 7Bshows a bottom-view of the product according to VIIB in FIG. 7A. In thisexample, output clamps 30N1 and 30N2 are connected with a respectivebackground domain portions 220A, 220B of the electrically conductivebackground domain Output clamps 30P1 and 30P2 are connected with arespective contact area 221, one within, but insulated from the firstbackground domain portion 220A and the other one within, but insulatedfrom the second background domain portion 220B. Therewith the currentdelivered during operation of the (separated) photovoltaic product 1A issplit into a current delivered through the pair of output clamps 30P1,30N1 and through the pair of output clamps 30P2, 30N2.

FIG. 8, 8A, 8B schematically show a portion of an exemplary photovoltaiclayer stack 10 on a substrate 12 that subsequently comprises a firstelectrically conductive layer 110, a photovoltaic layer 120 of aphotovoltaic material, for example a perovskite photovoltaic materialand a second electrically conductive layer 130, and a protective coating140 forming a barrier against moisture. Therein FIG. 8 show a view ofthe photovoltaic layer stack 10 at the side where it is to face theelectrically conductive layer stack 20 and FIGS. 8A, and 8B respectivelyshow a cross-section according to VIIIA-VIIIA in FIG. 8 and according toVIIIB-VIIIB in FIG. 8. As shown in particular in FIG. 8A, and as alsoschematically illustrated in FIG. 8, the first electrically conductivelayer 110 is partitioned into distinct portions along first partitioninglines L11, L12 extending in a first direction D2. In practice a width ofthe first partitioning lines may be in a range of 100 nm to 500 micron.Nevertheless additional partitions may be provided which are separatedat larger distances, e.g. a few cm. A space formed by the firstpartitioning lines may be filled with a filling material different froma material of the first electrically conductive layer 110. The fillingmaterial may be the perovskite photovoltaic material of the photovoltaiclayer 120. This is advantageous in that a separate filling step in themanufacturing process is superfluous. Alternatively an insulator may beused as the filler material, which has the advantage that thepartitioning lines can be relatively narrow. A partitioning of a layerdoes not necessarily imply a removal of material from the layer.Alternatively it is possible to convert a layer along a partitioningline, for example an electrically conductive layer may be partitionedinto mutually insulated areas by rendering the material non-conductivealong partitioning lines that separate the mutually insulated areas.E.g. an electrically conductive layer of SnOF (FTO) can be renderednon-conducting by a laser heating step that transforms the material toSnO.

As also shown in FIG. 8A, the second electrically conductive layer 130and the photovoltaic layer 120 are partitioned along second partitioninglines L21, L22 extending in the first direction D2. The secondelectrically conductive layer 130 and the photovoltaic layer 120 arefurther partitioned along third partitioning lines L31, L32 that extendin a direction D1 different from direction D2. In an embodiment thedirections D1, D2 are mutually orthogonal, but alternatively, thesedirections may differ by another angle, e.g. an angle selected in therange of 10 to 90 degrees.

As can be seen in FIGS. 8 and 8A, the first partitioning lines L11, L12and the second partitioning lines L21, L22 alternate each other.Furthermore, a space 150 defined by the first partitioning lines L11,L12 and the third partitioning lines L31, L32 is filled with aprotective filler material forming a barrier against moisture, therewithdefining photovoltaic cells encapsulated by the protective material ofthe coating 140 and the protective filler material. In this embodimentthe protective filler material in the space 150 is the same as theprotective material of the coating. The protective material may forexample comprise one or more of a ceramic material, such as SiN, Al2O3,TiO2, ZrO2. Also combinations are suitable, such as a combination of oneof TiO2, ZrO2 with Al2O3. In manufacturing the protective material forthe coating 140 and the space 150 may for example be provided in asingle deposition process, e.g. by a CVD process or an (s)ALD process.In the embodiment shown the depth of the first partitioning lines L11,L12 and the third partitioning lines L31, L32 may for example be in therange of 100 nm to 200 micron, and a width may be in a range of 1 micronto 50 centimeter. In the embodiment shown fourth partitioning lines L41,L42 are provided in the direction D2, one between each firstpartitioning line and a subsequent second partitioning line. The fourthpartitioning lines L41, L42 provide a space for an electrical connectionbetween a portion of the second electrically conductive layer 130defined by a cell (e.g. C12) and a portion of the first electricallyconductive layer 10 defined by a neighboring cell (e.g. C22). A suitablewidth of this space is for example in the order of 10 to 80 micron. Theelectrical connection may be provided by the electrically conductivematerial of the second electrically conductive layer 130 onto a surfaceof the first electrically conductive layer 110, or by anotherelectrically conductive material in the space provided by the fourthpartitioning lines. Therewith a series arrangement is formed of thecells C11, C12, C13 arranged along the second direction D1. These arestill connected by electrode 10 in this configuration. More examples canbe found in PCT/NL2018/050521, which was previously filed by the sameapplicant.

FIG. 9A shows an exemplary method to provide the photovoltaic layerstack of FIGS. 8, 8A and 8B with electrical connections.

In the example of FIG. 9A, a portion of the first electricallyconductive layer 110 is exposed at the boundary of two mutuallysubsequent photovoltaic device cells C31, C41. Therewith a respectiveportion of the first electrically conductive layer 110 of each of thesedevice cells C31, C41 is exposed. In this example, where the firstelectrically conductive layer 110 portions form the anode, the portionproper to device cell C31 forms a neutral contact 110N to a set ofserially arranged photovoltaic device cells C21, C11, etc and theportion proper to device cell C41 forms a positive contact 110P to a setof serially arranged photovoltaic device cells C51, . . . , etc. In casethat the first electrically conductive layer 110 portions form thecathode, the polarity of the contacts is reversely defined. To form thecontacts it is necessary to (at least partially) remove material fromthe other layers of at least the device cells C31. It is noted that inthis embodiment a positive and neutral contact 110N, 110P are relativelyclose to each other. This may complicate forming electric connectionswith their corresponding contacts in the first electrically conductivelayer 21 of the electrically conductive layer stack 20. It may becontemplated to not expose the contacts at the first electricallyconductive layer 110 portions of directly subsequent photovoltaic devicecells C31, C41, but instead select a pair of cells that is furtherapart, for example the pair of cells C21, C41. However, in that case theintermediary cells, would also disappear, or at least becomedysfunctional, which is at the cost of device efficiency.

An alternative approach is shown in FIG. 9B, 9C. In this case mutuallysubsequent photovoltaic units share a respective common electricalcontact. This is rendered possible in that the polarity of thephotodiodes Dp is reversed at each boundary between a photovoltaic unite.g. 11A and its direct successor, 11B, as is schematically shown inFIG. 2AB. In this example, photovoltaic device cells C11, and C21, mayfor example be the last two photodiodes of photovoltaic unit 11A, andphotovoltaic device cells C41, and C51, may for example be the first twophotodiodes of photovoltaic unit 11B. In FIG. 9C, photovoltaic devicecell C′11 may be the last photodiode of photovoltaic unit 11B and C′41may be the first photodiode of photovoltaic unit 11C. In this way issingle contact suffices between each pair of photovoltaic units 11A,11B; 11B, 11C etc. Therewith the distance between the contacts can berelatively large as the are separated by photovoltaic unit, whileavoiding that the functionality of the intermediate photovoltaic cellsis impaired. Hence the large separating space is efficiently used.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the invention. Asused herein, the singular forms “a”, “an” and “the” are intended toinclude the plural forms as well, unless the context clearly indicatesotherwise. It will be further understood that the terms “comprises”and/or “comprising,” when used in this specification, specify thepresence of stated features, integers, steps, operations, elements,and/or components, but do not preclude the presence or addition of oneor more other features, integers, steps, operations, elements,components, and/or groups thereof. Further, unless expressly stated tothe contrary, “or” refers to an inclusive or and not to an exclusive or.For example, a condition A or B is satisfied by any one of thefollowing: A is true (or present) and B is false (or not present), A isfalse (or not present) and B is true (or present), and both A and B aretrue (or present).

The invention claimed is:
 1. Photovoltaic product comprising: a foilwith a photovoltaic layer stack; and an electrically conductive layerstack that supports the photovoltaic layer stack and that, in anoperational state, provides for a transport of electric energy generatedby the photovoltaic layer stack to an external load, wherein theelectrically conductive layer stack comprises: a first electricallyconductive layer; a second electrically conductive layer; and anelectrically insulating layer arranged between the first electricallyconductive layer and the second electrically conductive layer, whereinthe first electrically conductive layer comprises: a first electricallyconductive background domain; and a first plurality of laterallydistributed, mutually distinct contact areas that are electricallyinsulated from the first electrically conductive background domain;wherein the second electrically conductive layer comprises: a secondelectrically conductive background domain; and a second plurality oflaterally distributed, mutually distinct contact areas that areelectrically insulated from the second electrically conductivebackground domain; wherein the electrically conductive layer stackfurther comprises: a first plurality of laterally distributedelectrically conducting vias that electrically interconnect respectiveones of the first plurality of contact areas with the secondelectrically conductive background domain; a second plurality oflaterally distributed electrically conducting vias that electricallyinterconnect respective ones of the second plurality of contact areaswith the first electrically conductive background domain; wherein thephotovoltaic layer stack has comprises: first electrical contacts of afirst polarity that are electrically connected to the first electricallyconductive background domain; and second electrical contacts of a secondpolarity opposite to said first polarity that are electrically connectedto the first contact areas, and wherein the second electricallyconductive background domain and one or more of the second contact areasserve as electric contacts for connecting the photovoltaic product to anexternal load.
 2. The photovoltaic product of claim 1, wherein thesecond contact areas are at least twice as large as the first contactareas.
 3. The photovoltaic product of claim 1, wherein the photovoltaiclayer comprises a plurality of photovoltaic units that are arranged inan arrangement direction, such that mutually subsequent photovoltaicunits share a respective common electrical contact.
 4. The photovoltaicproduct according to claim 3, further comprising diodes that arearranged: between the first electrical contacts and the firstelectrically conductive background domain; and/or between the secondelectrical contacts and the first contact areas, wherein the diodes arebiased in accordance with current direction as determined by theplurality of photovoltaic units in their normal operational state. 5.The photovoltaic product according to claim 1, wherein the firstelectrically conductive background domain and/or the second electricallyconductive background domain is partitioned into mutually separatebackground domain portions which that are separated from each otherthrough an elongate region free from electrically conductive materialextending in a direction transverse to an arrangement direction in whichthe photovoltaic units succeed each other.
 6. The photovoltaic productaccording to claim 5, further comprising a respective pair of outputclamps attached at each lateral portion of the photovoltaic productcorresponding to a proper one of the background domain portions of thefirst electrically conductive background domain and the secondelectrically conductive background domain.
 7. A method of manufacturinga photovoltaic product, comprising: providing a photovoltaic layer stackhaving a plurality of photovoltaic units, and having first electricalcontacts of a first polarity and second electrical contacts of a secondpolarity opposite t//o said first polarity; providing an electricallyconductive layer stack; laminating the photovoltaic layer stack on theelectrically conductive layer stack; wherein the providing anelectrically conductive layer stack comprises: providing an insulatinglayer with a first electrically conductive layer and a secondelectrically conductive layer at respective ones of mutually oppositesurfaces of the insulating layer; providing a first plurality oflaterally distributed electrically conducting vias that electricallyinterconnect the first electrically conductive layer and the secondelectrically conductive layer; providing a second plurality of laterallydistributed electrically conducting vias that electrically interconnectthe first electrically conductive layer and the second electricallyconductive layer; removing material of the first electrically conductivelayer along a contour of a zone around each via of the first plurality,to partition the first electrically conductive layer into: a firstelectrically conductive background domain, and a first plurality oflaterally distributed, mutually distinct contact areas that areelectrically insulated from the first electrically conductive backgrounddomain; removing material of the second electrically conductive layeralong a contour of a zone around each via of the second plurality, topartition the second electrically conductive layer into: a secondelectrically conductive background domain, and a second plurality oflaterally distributed, mutually distinct contact areas which that areelectrically insulated from the second electrically conductivebackground domain; and wherein said laminating comprises interconnectingthe first electrical contacts of the photovoltaic layer stack with thefirst electrically conductive background domain of the firstelectrically conductive layer and interconnecting the second electricalcontacts to respective first contact areas of the first electricallyconductive layer.
 8. The method of claim 7, comprising arranging diodesat the first electrically conductive background domain at the locationsdetermined for interconnection with the first electrical contacts of thephotovoltaic layer stack and/or at the locations of the first contactareas for interconnection with the second electrical contacts of thephotovoltaic layer stack.
 9. The method of claim 7, comprising applyinga layer of a polymer melt material on the first electrically conductivelayer as an interface between the electrically conductive layer stackand the photovoltaic layer stack to be laminated therewith.
 10. Themethod of claim 7, comprising providing a protective layer over thesecond electrically conductive layer.
 11. The method of claim 10,comprising providing the protective layer with markings, each markingbeing indicative of a location of one or more of the contact areas inthe second electrically conductive layer.
 12. The method according toclaim 7, comprising, separating a lateral portion of the photovoltaicproduct, to obtain a separated photovoltaic product.
 13. The methodaccording to claim 7, comprising partitioning the first electricallyconductive background domain and/or the second electrically conductivebackground domain into mutually separate background domain portions byremoving material of the first and/or the second electrically conductivelayer along an elongate region extending in a direction transverse to anarrangement direction in which the photovoltaic units succeed eachother.
 14. The photovoltaic product of claim 1 wherein the secondelectrically conductive background domain and one or more of the secondcontact areas serve as electric contacts for connecting the photovoltaicproduct to an external load via output clamps.